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81.
A. C. Chaves N. Lucena-Silva F. G. C. Abath V. R. A. Pereira J. L. Lima-Filho A. L. F. Porto J. M. S. Cabral 《Bioprocess and biosystems engineering》2000,23(5):435-438
This work describes the partition of a Schistosoma mansoni tegumental antigen produced by a recombinant Escherichia coli strain using an aqueous two-phase system composed of polyethylene glycol (PEG) and potassium phosphate. The effects of the polymer molecular weight, tie line length and pH on antigen partitioning were investigated. The detection of the antigen in both phases were determined by ELISA. The system composed of PEG 3550 (19.7% w/w) and potassium phosphate (17.7% w/w) led to a yield of 59% and an antigen purification factor of 3 in the PEG-rich phase. It was observed that the antigen partition in ATPS was strongly affected by the pH value and tie line length. In addition, it was possible in a single step, to remove the cell debris, that precipitated at the interface of the system. 相似文献
82.
Alex F. de Vos Mark C. Dessing Adriana J. J. Lammers Alexander P. N. A. de Porto Sandrine Florquin Onno J. de Boer Regina de Beer Sanne Terpstra Hester J. Bootsma Peter W. Hermans Cornelis van ‘t Veer Tom van der Poll 《PloS one》2015,10(2)
Toll-like receptors (TLR) and the downstream adaptor protein MyD88 are considered crucial for protective immunity during bacterial infections. Streptococcus (S.) pneumoniae is a human respiratory pathogen and a large majority of clinical pneumococcal isolates expresses an external polysaccharide capsule. We here sought to determine the role of pneumococcal capsule in MyD88-mediated antibacterial defense during S. pneumonia pneumonia. Wild type (WT) and Myd88-/- mice were inoculated intranasally with serotype 2 S. pneumoniae D39 or with an isogenic capsule locus deletion mutant (D39∆cps), and analysed for bacterial outgrowth and inflammatory responses in the lung. As compared to WT mice, Myd88-/- mice infected with D39 demonstrated a modestly impaired bacterial clearance accompanied by decreased inflammatory responses in the lung. Strikingly, while WT mice rapidly cleared D39∆cps, Myd88-/- mice showed 105-fold higher bacterial burdens in their lungs and dissemination to blood 24 hours after infection. These data suggest that the pneumococcal capsule impairs recognition of TLR ligands expressed by S. pneumoniae and thereby partially impedes MyD88-mediated antibacterial defense. 相似文献
83.
Linkage disequilibrium over short physical distances measured in sheep using a high‐density SNP chip
James W. Kijas Laercio Porto‐Neto Sonja Dominik Antonio Reverter Rowan Bunch Russell McCulloch Ben J. Hayes Rudiger Brauning John McEwan the International Sheep Genomics Consortium 《Animal genetics》2014,45(5):754-757
The extent of linkage disequilibrium (LD) between genetic loci has implications for both association studies and the accuracy of genomic prediction. To characterise the persistence of LD in diverse sheep breeds, two SNP genotyping platforms were used. First, existing SNP genotypes from 63 breeds obtained using the ovine SNP50 BeadChip (49 034 loci) were used to estimate LD decay in populations with contrasting levels of genetic diversity. Given the paucity of marker pairs separated by short physical distances on the SNP50 BeadChip, genotyping was subsequently performed for four breeds using the recently developed ovine HD BeadChip that assays approximately 600 000 SNPs with an average genomic spacing of 5 kb. This facilitated a highly accurate estimate of LD over short genomic distances (<30 kb) and revealed LD varies considerably between sheep breeds. Further, sheep appear to contain generally lower levels of LD than do other domestic species, likely a reflection of aspects of their past population history. 相似文献
84.
Climatic data from 444 weather-recording stations in the Mediterranean basin are examined by cluster analysis and principal component analysis. The application of numerical clustering distinguished several groups of climatic stations clearly interpretable in geographic and climatic terms. The hierarchical structure of the dendrograms could be used to identify at different scales uniform climatic regions. The complementary application of principal component analysis produced an ordination of climatic types, which clearly showed the main trends of variation in the precipitation and temperature patterns. 相似文献
85.
Five cases of paracoccidioidomas are reviewed. One case with multiple coin-lesions simulating Wegener's granulomatosis is described.From the Pavilhão Pereira Filho, Santa Casa de Misericórdia, Porto Alegre, RS, Brazil. 相似文献
86.
Keila?Cristina?Novais?Porto Yule?Roberta?Ferreira?Nunes Leonardo?Monteiro?RibeiroEmail author 《Plant Ecology》2018,219(2):199-207
The Mauritia flexuosa palm tree is widely distributed in South America, and is associated with flooded environments. It dominates the arboreal stratum in the highly threatened marsh ecosystems called “veredas” in the Cerrado biome (neotropical savanna), and its oleaginous fruits are important for the maintenance of the regional fauna and as a source of income for traditional human populations. The seeds of this palm demonstrate an unusual association of recalcitrance and dormancy, and information about its seed bank maintenance in natural environments is scarce. We measured the variations in water content, viability, and germination of seeds maintained over 1 year in four typical vereda microenvironments (edge, near the water, in the water, and at the lower zone of the vereda) and related that information to soil water contents and climatic data. Seed viability was best preserved under constantly flooded conditions (at the lower zone of the vereda), with the potential for maintaining a temporary seed bank in the aquatic environment that would favor dispersal. Although the seeds are intolerant of dehydration, they have a high capacity for maintaining their water contents under partially drained soil conditions, and overcoming dormancy is favored under those conditions. Mauritia flexuosa establishment strategies are driven by sophisticated interactions with climate and with vereda microenvironments, with a tendency for maintaining seed banks and seedling banks in localities with flooded or drained soils, respectively. 相似文献
87.
First record of non‐native hybrid catfish Pseudoplatystoma reticulatum × Leiarius marmoratus in the Upper Paraná River basin,Brazil 下载免费PDF全文
M. H. S. Yabu A. P. Vidotto‐Magnoni A. C. R. Casimiro D. A. Z. Garcia A. D. A. Costa F. D. D. Prado F. Porto‐Foresti M. L. Orsi 《Journal of fish biology》2018,92(1):261-267
The aim of this study is to report the presence of a three non‐native hybrid long‐whiskered catfishes (family Pimelodidae) in the Upper Paraná River basin, Brazil. Genetic analyses demonstrated that the three presumptive hybrids were a result of the crossbreeding of Pseudoplatystoma reticulatum (central Amazonas River basin and Lower Paraná River) and Leiarius marmoratus (Amazonas, Essequibo and Orinoco rivers), producing a hybrid commonly known in Brazil as cachandiá. The potential threat to biodiversity, due to possible genetic contamination, competition and predation of wild stocks, of such artificially produced hybrid fishes is discussed. 相似文献
88.
William F. Porto Isabel C.M. Fensterseifer Suzana M. Ribeiro Octavio L. Franco 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(9):2043-2052
Innovative alternatives to control bacterial infections are need due to bacterial resistance rise. Antimicrobial peptides (AMPs) have been considered as the new generation of antimicrobial agents. Based on the fact that AMPs are sequence-dependent, a linguistic model for designing AMPs was previously developed, considering AMPs as a formal language with a grammar (patterns or motifs) and a vocabulary (amino acids). Albeit promising, that model has been poorly exploited mainly because thousands of sequences need to be generated, and the outcome has high similarity to already known AMPs. Here we present Joker, an innovative algorithm that improves the application of the linguistic model for rational design of antimicrobial peptides. We modelled the AMPs as a card game, where Joker combines the cards in the hand (patterns) with the cards in the table (sequence templates), generating a few variants. Our algorithm is capable of improving existing AMPs or even creating new AMPs from inactive peptides. A standalone version of Joker is available for download at <http://github.com/williamfp7/Joker> and requires a Linux 32-bit machine. 相似文献
89.
Selenium Utilization by GPX4 Is Required to Prevent Hydroperoxide-Induced Ferroptosis 总被引:1,自引:0,他引:1
Irina Ingold Carsten Berndt Sabine Schmitt Sebastian Doll Gereon Poschmann Katalin Buday Antonella Roveri Xiaoxiao Peng Florencio Porto Freitas Tobias Seibt Lisa Mehr Michaela Aichler Axel Walch Daniel Lamp Martin Jastroch Sayuri Miyamoto Wolfgang Wurst Fulvio Ursini Marcus Conrad 《Cell》2018,172(3):409-422.e21
90.